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#[derive(Copy, Clone, PartialEq, PartialOrd)]
pub enum File {
A,
B,
C,
D,
E,
F,
G,
H,
}
pub const NUM_FILES: usize = 8;
pub const ALL_FILES: [File; NUM_FILES] = [File::A, File::B, File::C, File::D, File::E, File::F, File::G, File::H];
impl File {
pub fn from_index(i: usize) -> File {
unsafe {
*ALL_FILES.get_unchecked(i & 7)
}
}
pub fn left(&self) -> File {
File::from_index(self.to_index().wrapping_sub(1))
}
pub fn right(&self) -> File {
File::from_index(self.to_index() + 1)
}
pub fn to_index(&self) -> usize {
*self as usize
}
}